Pump

ABSTRACT

A pump includes a main body having upper and lower body parts that confine a chamber and an inlet, respectively, an inlet valve including a valve seat and a ball member seated movably on the valve seat to block fluid communication between the inlet and the chamber, a delivery shaft including a valve-control segment and a delivery segment that is formed with a channel to be disposed in fluid communication with the chamber, a piston disposed movably in the chamber, an elastic component disposed in the main body for providing a biasing force to move the valve-control segment of the delivery shaft away from the inlet valve, and a delivery tube operable to drive movement of the delivery shaft toward the inlet valve such that the valve-control segment forces the ball member to be seated on the valve seat.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a pump, more particularly to a pump adapted to dispense liquid from a container.

2. Description of the Related Art

As shown in FIG. 1 and FIG. 2, a container assembly for a liquid, such as shampoo, lotion, etc., includes a container (not shown) for receiving the liquid, a conventional pump 10, and a nozzle assembly 17 including a nozzle 171, a cap 172, and a riser tube 174 (partially shown in FIG. 1) . The nozzle 171 and the riser tuber 174 are coupled to the conventional pump 10 at opposite ends, respectively. The conventional pump 10 is movable together with the nozzle 171 relative to the container such that the liquid in the container can be dispensed from the container through the riser tube 174 and out of the nozzle 171.

The conventional pump 10 includes a tubular main body 11, an inlet valve 12, a delivery shaft 13, a piston 14, an elastic component 16, and a delivery tube 15.

The main body 11 extends along an axis (X) and has an upper body part 111 confining a chamber 113, and a lower body part 112 connected to the upper body part 111 and confining an inlet 114 distal from the upper body part 111.

The inlet valve 12 includes a valve seat 121 formed in the lower body part 112, and a ball member 122 disposed in the lower body part 112 and seated movably on the valve seat 121 to block fluid communication between the inlet 114 and the chamber 113.

The delivery shaft 13 extends through the upper body part 111 into the chamber 113 along the axis (X), and includes an upper delivery segment 131, and a lower piston-seating segment 133 connected to the delivery segment 131. The delivery segment 131 is formed with two channels 132 to be disposed in fluid communication with the chamber 113.

The piston 14 is disposed movably in the chamber 113 along the axis (X), and includes a sleeve portion 141 sleeved on the delivery segment 131 of the delivery shaft 13, a peripheral portion 142 disposed around the sleeve portion 141 and in sealing contact with the upper body part 111, and a connecting portion 143 that interconnects the sleeve and peripheral portions 141, 142.

The elastic component 16 is a compression spring that is disposed in the main body 11, that is sleeved on the piston-seating segment 133 of the delivery shaft 13, and that has opposite ends that abut against the lower body part 112 and the piston-seating segment 133, respectively. The elastic component 16 provides a biasing force to move the delivery shaft 13 away from the inlet valve 12, and to cause the piston-seating segment 133 to push the sleeve portion 141 of the piston 14 away from the inlet valve 12.

The delivery tube 15 is sleeved on the delivery segment 131 of the delivery shaft 13, is connected to the nozzle 171, and is spaced apart from the piston 14 at a separation distance (D) . The delivery tube 15 is operable to drive movement of the delivery shaft 13 toward the inlet valve 12 against urging action of the elastic component 16.

As shown in FIG. 3, to dispense the liquid from the container, the nozzle 171 is pressed downwardly along the axis (X) to actuate the delivery tube 15 to push the delivery shaft 13 toward the inlet valve 12 until the delivery tube 15 abuts against the sleeve portion 141 of the piston 14, at which point the piston-seating segment 133 of the delivery shaft 13 is spaced apart from the sleeve portion 141 of the piston 14 at the separation distance (D) due to pressure in the chamber 113, such that the channels 132 are in fluid communication with the chamber 113. The nozzle 171 is pressed downwardly in the direction as illustrated by arrow (A) along the axis (X) further to actuate the delivery tube 15 to push the delivery shaft 13 and the piston 14 toward the inlet valve 12. At the same time, the elastic component 16 is compressed, and the pressure in the chamber 113 is increased, such that the liquid in the chamber 113 is dispensed through the channels 132 out of the nozzle 171.

As shown in FIG.4, when the nozzle 171 is released, the biasing force of the elastic component 16 moves the delivery shaft 13 away from the inlet valve 12 in the direction as illustrated by arrow (B), and causes the piston-seating segment 133 of the delivery shaft 13 to abut against the sleeve portion 141 of the piston 14 away from the inlet valve 12, such that fluid communication between the channels 132 and the chamber 113 is prevented. Due to pressure difference inside the chamber 113 and the riser tube 174, the ball member 122 moves away from the valve seat 121, such that the inlet 114 is in fluid communication with the chamber 113 to permit flow of the liquid from the container into the chamber 113. As the pressure inside the chamber 113 and that inside the riser tube 174 reach equilibrium, the ball member 122 is seated once more on the valve seat 121 such that fluid communication between the inlet 114 and the chamber 113 is blocked once again, as best illustrated in FIG. 1.

As shown in FIG. 5, when the liquid is highly viscous, it is likely to accumulate on the valve seat 121, such that the ball member 122 cannot be properly seated thereon to block fluid communication between the inlet 114 and the chamber 113. As result, the liquid cannot be dispensed from the container.

SUMMARY OF THE INVENTION

Therefore, the object of the present invention is to provide a pump that is adapted to dispense highly viscous liquids from a container.

According to the present invention, there is provided a pump that includes a tubular main body, an inlet valve, a delivery shaft, a piston, an elastic component, and a delivery tube. The main body extends along an axis and has an upper body part confining a chamber, and a lower body part connected to the upper body part and confining an inlet distal from the upper body part. The inlet valve includes a valve seat formed in the lower body part, and a ball member disposed in the lower body part and seated movably on the valve seat to block fluid communication between the inlet and the chamber. The delivery shaft extends through the upper body part into the chamber along the axis, and includes an upper delivery segment, a lower valve-control segment, and a piston-seating segment disposed between the delivery and valve-control segments. The delivery segment of the delivery shaft is formed with a channel to be disposed in fluid communication with the chamber. The piston is disposed movably in the chamber and includes a sleeve portion sleeved on the delivery segment of the delivery shaft, a peripheral portion disposed around the sleeve portion and in sealing contact with the upper body part, and a connecting portion that interconnects the sleeve and peripheral portions. The elastic component is disposed in the main body for providing a biasing force to move the valve-control segment of the delivery shaft away from the inlet valve, and to cause the piston-seating segment of the delivery shaft to push the sleeve portion of the piston away from the inlet valve. The delivery tube is sleeved on the delivery segment of the delivery shaft, and is operable to drive movement of the delivery shaft toward the inlet valve such that the valve-control segment of the delivery shaft forces the ball member to be seated on the valve seat, and to drive movement of the piston toward the inlet valve.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiments with reference to the accompanying drawings, of which:

FIG. 1 is a sectional view of a conventional pump coupled to a nozzle assembly;

FIG. 2 is a top sectional view taken along line II-II in FIG. 1;

FIG. 3 is a sectional view similar to FIG. 1, illustrating pressing of a nozzle;

FIG. 4 is a sectional view similar to FIG. 1, illustrating releasing of the nozzle;

FIG. 5 is a sectional view similar to FIG. 1, illustrating a drawback of the conventional pump;

FIG. 6 is a sectional view of the first preferred embodiment of a pump coupled to a nozzle assembly according to the present invention;

FIG. 7 is a top sectional view of the first preferred embodiment taken along line VII-VII in FIG. 6;

FIG. 8 is a sectional view of the first preferred embodiment, illustrating pressing of a nozzle;

FIG. 9 is a sectional view of the first preferred embodiment, illustrating releasing of the nozzle;

FIG. 10 is a top sectional view of the second preferred embodiment of a pump according to the present invention;

FIG. 11 is a sectional view of the third preferred embodiment of a pump coupled to a nozzle assembly according to the present invention;

FIG. 12 is a sectional view of the third preferred embodiment, illustrating pressing of a nozzle;

FIG. 13 is a sectional view of the fourth preferred embodiment of a pump coupled to a nozzle assembly according to the present invention; and

FIG. 14 is a sectional view of the fifth preferred embodiment of a pump coupled to a nozzle assembly according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Before the present invention is described in greater detail, it should be noted herein that like elements are denoted by the same reference numerals throughout the disclosure.

As shown in FIG. 6 and FIG. 7, the first preferred embodiment of a pump 200 according to the present invention is adapted to be coupled to the conventional nozzle assembly 17 of FIG. 1. The pump 200 includes a tubular main body 20, an inlet valve 30, a delivery shaft 40, a piston 50, an elastic component 70, and a delivery tube 60.

The tubular main body 20 extends along the axis (X) and has an upper body part 201 confining a chamber 203, and a lower body part 202 connected to the upper body part 201 and confining an inlet 204 distal from the upper body part 201. In this embodiment, the upper body part 201 has a larger cross-section than that of the lower body part 202. In addition, the main body 20 further has a shoulder part 205 between the upper and lower body parts 201, 202.

The inlet valve 30 includes a valve seat 301 formed in the lower body part 202, and a ball member 302 disposed in the lower body part 202 and seated movably on the valve seat 301 to block fluid communication between the inlet 204 and the chamber 203.

The delivery shaft 40 extends through the upper body part 201 into the chamber 203 along the axis (X), and includes an upper delivery segment 401, a lower valve-control segment 402, and a piston-seating segment 403 disposed between the delivery and valve-control segments 401, 402. The delivery segment 401 is formed with a channel 404 to be disposed in fluid communication with the chamber 203. In this embodiment, the delivery, valve-control, and piston-seating segments 401, 402, 403 are formed integrally. The valve-control segment 402 includes an upper portion 4021 and a lower portion 4022 having a cross-section smaller than that of the upper portion 4021. The delivery shaft 40 has a length such that when the piston-seating segment 403 of the delivery shaft 40 abuts against the shoulder part 205 of the main body 20, the valve-control segment 402 of the delivery shaft 40 abuts against the ball member 302, thereby forcing the ball member 302 to be seated on the valve seat 301 to block fluid communication between the inlet 204 and the chamber 203, as best shown in FIG. 8.

The piston 50 is disposed movably in the chamber 203, and includes a sleeve portion 501 sleeved on the delivery segment 401 of the delivery shaft 40, a peripheral portion 502 disposed around the sleeve portion 501 and in sealing contact with the upper body part 201, and a connecting portion 503 that interconnects the sleeve and peripheral portions 501, 502. Fluid communication between the channel 404 and the chamber 203 is prevented when the piston-seating segment 403 of the delivery shaft 40 abuts against the sleeve portion 501 of the piston 50.

The elastic component 70 is disposed in the main body 20 for providing a biasing force to move the valve-control segment 402 of the delivery shaft 40 away from the inlet valve 30, and to cause the piston-seating segment 403 of the delivery shaft 40 to push the sleeve portion 501 of the piston 50 away from the inlet valve 30. In this embodiment, the elastic component 70 is a compression spring that is sleeved on the valve-control segment 402 of the delivery shaft 40, and that has opposite ends abutting against the lower body part 202 and the piston-seating segment 403, respectively.

The delivery tube 60 is sleeved on the delivery segment 401 of the delivery shaft 40, and is spaced apart from the piston 50 at a separation distance (D). As best shown in FIG. 8, the delivery tube 60 is operable via the nozzle 171 to drive movement of the delivery shaft 40 toward the inlet valve 30 against urging action of the elastic component 70, such that the valve-control segment 402 of the delivery shaft 40 forces the ball member 302 to be seated on the valve seat 301, and to drive movement of the piston 50 toward the inlet valve 30. Pressure in the chamber 203 when the piston 50 is driven by the delivery tube 60 toward the inlet valve 30 causes the sleeve portion 501 of the piston 50 to move away from the piston-seating segment 403 of the delivery shaft 40 to permit fluid communication between the channel 404 and the chamber 203.

In this embodiment, the shoulder part 205 of the main body 20 cooperates with the piston-seating segment 403 of the delivery shaft 40 to limit movement of the delivery shaft 40 toward the inlet valve 30 upon operation of the delivery tube 60 via the nozzle 171. In addition, as best shown in FIG. 7, the delivery segment 401 of the delivery shaft 40 has an outer surface 406, and the channel 404 includes four fluid ducts 405 that extend parallel to the axis (X), that are angularly spaced apart from each other relative to the axis (X), and that are indented from the outer surface 406 of the delivery segment 401 toward the axis (X).

As shown in FIG. 8 and FIG. 9, the pump 200 is coupled to the nozzle assembly 17 that includes the nozzle 171 and the cap 172, and is applied to a container (not shown) filled with a liquid (not shown). The following steps are taken when the liquid is to be dispensed from the container.

(1) The nozzle 171 is pressed downwardly in the direction as illustrated by arrow (C) along the axis (X) to actuate the delivery tube 60 to push the delivery shaft 40 toward the inlet valve 30 until the delivery tube 60 abuts against the sleeve portion 501 of the piston 50, at which point the piston-seating segment 403 of the delivery shaft 40 is spaced apart from the sleeve portion 501 of the piston 50 at the separation distance (D) due to pressure in the chamber 203, such that the channel 404 is in fluid communication with the chamber 203, as best illustrated in FIG.8.

(2) The nozzle 171 is pressed downwardly in the direction as illustrated by arrow (C) along the axis (X) further to actuate the delivery tube 60 to push the delivery shaft 40 and the piston 50 toward the inlet valve 30 until the piston-seating segment 403 of the delivery shaft 40 abuts against the shoulder 205 of the main body 20, at which point, the valve-control segment 402 of the delivery shaft 40 forces the ball member 302 to be seated on the valve seat 301. At the same time, the elastic component 70 is compressed, and the pressure in the chamber 203 is increased, such that the liquid in the chamber 203 is dispensed through the channel 404 out of the nozzle 171, as best illustrated in FIG. 8.

(3) The nozzle 171 is released so that the biasing force of the elastic component 70 moves the delivery shaft 40 away from the inlet valve 30 in the direction as illustrated by arrow (E), and causes the piston-seating segment 403 of the delivery shaft 40 to abut against the sleeve portion 501 of the piston 50 away from the inlet valve 30, such that fluid communication between the channel 404 and the chamber 203 is prevented. At the same time, the delivery shaft 40 and the piston 50 are pushed upward along the axis (X) in the direction as illustrated by arrow (E) . Due to pressure difference inside the chamber 203 and the riser tube 174, the ball member 302 moves away from the valve seat 301, such that the inlet 204 is in fluid communication with the chamber 203 to permit flow of the liquid from the container into the chamber 203, as best shown in FIG.9.

Since the valve-control segment 402 of the delivery shaft 40 forces the ball member 302 to be seated on the valve seat 301 when dispensing the liquid from the chamber 203, the liquid can be drawn from the container into the chamber 203 when the nozzle 171 is subsequently released.

Therefore, by ensuring a suitable length for the delivery shaft 40, such that the valve-control segment 402 is capable of forcing the ball member 302 to be seated on the valve seat 301, the pump 200 is clear of the drawback of the prior art regardless of the weight of the ball member 302 and the viscosity of the liquid in the container.

As shown in FIG. 10, the second preferred embodiment of a pump 200′ according to the present invention differs from the first preferred embodiment in that the channel 404′ includes three, instead of four, fluid ducts 405′ that extend parallel to the axis (X), that are angularly spaced apart from each other relative to the axis (X), and that are indented from the outer surface 406′ of the delivery segment 401′ of the delivery shaft 40′ toward the axis (X).

As shown in FIG. 11, the third preferred embodiment of a pump 200″ according to the present invention differs from the first preferred embodiment in that the channel 404″ includes one, instead of four, fluid duct 405″ that extends along the axis (X). In addition, the delivery segment 401″ of the delivery shaft 40″ is further formed with a radial port 407 to communicate fluidly the channel 404″ and the chamber 203, as shown in FIG. 12.

As shown in FIG. 13, the fourth preferred embodiment of a pump 200 a according to the present invention differs from the first preferred embodiment in that the valve-control segment 402 a of the delivery shaft 40 a has a uniform cross-section.

As shown in FIG. 14, the fifth preferred embodiment of a pump 200 b according to the present invention differs from the first preferred embodiment in that the upper portion 4021 b of the valve-control segment 402 b of the delivery shaft 40 b is formed with a plurality of troughs 4023.

While the present invention has been described in connection with what is considered the most practical and preferred embodiments, it is understood that this invention is not limited to the disclosed embodiments but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation and equivalent arrangements. 

1. A pump comprising: a tubular main body extending along an axis and having an upper body part confining a chamber, and a lower body part connected to said upper body part and confining an inlet distal from said upper body part; an inlet valve including a valve seat formed in said lower body part, and a ball member disposed in said lower body part and seated movably on said valve seat to block fluid communication between said inlet and said chamber; a delivery shaft extending through said upper body part into said chamber along said axis, and including an upper delivery segment, a lower valve-control segment, and a piston-seating segment disposed between said delivery and valve-control segments, said delivery segment being formed with a channel to be disposed in fluid communication with said chamber; a piston disposed movably in said chamber and including a sleeve portion sleeved on said delivery segment of said delivery shaft, a peripheral portion disposed around said sleeve portion and in sealing contact with said upper body part, and a connecting portion that interconnects said sleeve and peripheral portions; an elastic component disposed in said main body for providing a biasing force to move said valve-control segment of said delivery shaft away from said inlet valve, and to cause said piston-seating segment of said delivery shaft to push said sleeve portion of said piston away from said inlet valve; and a delivery tube sleeved on said delivery segment of said delivery shaft and operable to drive movement of said delivery shaft toward said inlet valve such that said valve-control segment of said delivery shaft forces said ball member to be seated on said valve seat, and to drive movement of said piston toward said inlet valve.
 2. The pump as claimed in claim 1, wherein fluid communication between said channel and said chamber is prevented when said piston-seating segment of said delivery shaft abuts against said sleeve portion of said piston, pressure in said chamber when said piston is driven by said delivery tube toward said inlet valve causing said sleeve portion of said piston to move away from said piston-seating segment of said delivery shaft to permit fluid communication between said channel and said chamber.
 3. The pump as claimed in claim 1, wherein said upper body part has a larger cross-section than that of said lower body part, said main body further having a shoulder part between said upper and lower body parts, said shoulder part cooperating with said piston-seating segment of said delivery shaft to limit movement of said delivery shaft toward said inlet valve upon operation of said delivery tube.
 4. The pump as claimed in claim 1, wherein said delivery segment of said delivery shaft has an outer surface, and said channel includes at least three fluid ducts that extend parallel to said axis, that are angularly spaced apart from each other relative to said axis, and that are indented from said outer surface of said delivery segment toward said axis.
 5. The pump as claimed in claim 1, wherein said channel extends along said axis, and said delivery segment is further formed with a radial port to communicate fluidly said channel and said chamber.
 6. The pump as claimed in claim 1, wherein said elastic component is a compression spring sleeved on said valve-control segment of said delivery shaft and having opposite ends that abut against said lower body part of said main body and said piston-seating segment of said delivery shaft, respectively. 